The Southern Uralides are a collisional orogen generated in the Late Devonian–
Early Carboniferous by the collision of the Magnitogorsk island arc (MA) generated in the
Early to Middle Devonian by intra-oceanic convergence opposite to the continental margin,
and the continental margin of the East European craton. A suture zone of the arc to the
continental margin, the Main Uralian Fault (MUF), is marked by ophiolites and exhumed
high-pressure–low-temperature metamorphic rocks of continental origin. The preorogenic
events of the Southern Urals and their geodynamic setting are traced by means
of fluid-immobile incompatible trace elements (rare earth elements and high field strength
elements) and Sr–Nd–Pb isotope geochemistry of the MA suites, in particular the protoarc
suite with boninites and probably ankaramites, and the mature arc comprised of island arc
tholeiitic (IAT) suites, transitional IAT to calc-alkaline (CA), and CA suites. The MA
volcanics result in genetically distinct magmatic source components. In particular, depleted
normal-mid-oceanic ridge basalt-type mantle sources with various enrichments in a slabderived
aqueous fluid component are evident. The enriched component is not involved in
significant amounts, as testified by the rather radiogenic Nd isotopes and unradiogenic Pb
isotopes. Further information on the pre-orogenic events is provided by the Mindyak
Massif metagabbros derived from diverse gabbroic protoliths that were affected by oceanic
rodingitization, and subsequently by a high-temperature (HT) metamorphism related to
the development of a metamorphic sole. The HT metamorphism has the same age as the
protoarc volcanism, and constrains the initiation of subduction at approximately 410 Ma.
Consequently, the maximum timespan between initial intra-oceanic convergence and final
collision is approximately 31 my, a duration consistent with that of present-day ongoing
collisions in the western Pacific. The characteristics of early volcanism and the traces of a
metamorphic sole provide useful criteria to attribute most MUF ophiolites to the Tethyan
type with a complex pre-orogenic evolution.